Chapter 4. Ladder Diagram (LD) Programming
GFK-2950C
February 2018
167
MOVE_TO_FLAT Operands
Parameter Description
Allowed Operands
Optional
Length (??) The length of IN; the number of elements to copy.
1
Length
32,767
Constant
No
DC
Data coherency.
If True, the memory being written to is locked. This
enables a coherent copy of a UDT to reference memory.
If False (default), data is copied normally from one
Controller memory area to another; that is
without
data
coherency.
▪
DC should be used only when using interrupt
blocks and is required only when the same memory
is used in more than one interrupt block, or in the
main program and an interrupt block.
▪
If DC is True, an interrupt block cannot preempt the
copy operation.
▪
If DC is False or not present, interrupts can
preempt the copy.
▪
Using DC can impact interrupt latency if the
amount of data copied is large.
Data flow.
Yes
IN
UDT variable or UDT array. The data copied to the
reference memory mapped to the variable assigned to
Q.
If IN is 0, length is assigned the constant 1 and the
variable or structure assigned to Q is set to its default
value.
Discrete or non-discrete
symbolic, discrete or non-
discrete I/O variable.
No
Q
Variable or array to which IN is copied. The amount of
data copied is determined by the constant value
assigned to input LEN (Length).
All memory areas except %S,
discrete symbolic, discrete I/O
variable.
▪
Indirect referencing is
available for all register
references (%R, %P, %L,
%W, %AI, and %AQ).
▪
BYTE arrays must be
packed; that is, they must
be in discrete memory.
No
Example
A UDT variable or UDT array is assigned to input IN.
The constant value 8 is assigned to input LEN (Length).
A DWORD variable mapped to %R1 is assigned to output Q.
If the constant value 8 is assigned to LEN (length), there should be a UDT array of at least eight
elements assigned to IN. When MOVE_TO_FLAT executes,
n
bytes of data are copied from the UDT
variable or array to %R memory, starting at %R1 in the example, where
n
is the length of a UDT array
element (in bytes) times eight.
Summary of Contents for PACSystems RSTi-EP
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